Dysregulated circRNA_100876 contributes to proliferation and metastasis of colorectal cancer by targeting microRNA-516b (miR-516b).

Colorectal cancer (CRC) is globally one of the most common malignant tumors. Increasing number of studies indicate that circular RNAs (circRNAs) play a significant role in the initiation and progression of CRC. However, the role of circRNA_100876 in CRC progression remains unclear. In this study, we investigated the expression and function of circRNA_100876 in CRC progression. The expression of circRNA_100876 and microRNA-516b (miR-516b) was compared in normal and CRC tissues using quantitative real-time polymerase chain reaction (RT-qPCR). In addition, proliferation, metastasis, and apoptosis of the cells were analyzed using Cell Counting Kit-8 (CCK-8) assay, Transwell assay, and flow cytometry, respectively. The relationship between circRNA_100876 and miR-516b was further verified using dual-luciferase reporter assay. Our data showed that circRNA_100876 was highly expressed in CRC tumor tissues, and the high expression gtransition (EMT)-related proteins. Furthermore, we found that the addition of miR-516b reversed the anti-tumor effect induced by the downregulation of circRNA_100876. In conclusion, this study revealed that circRNA_100876 is overexpressed in CRC tissues and represents a promising therapeutic target for CRC.

Apatinib enhances the anti-tumor effect of cisplatin on gastric cancer by inhibiting HMGA2 / 中国肿瘤生物治疗杂志

@#[Abstract] Objective: To investigate the effect of apatinib (APA) combined with cisplatin (DDP) on the proliferation, invasion and migration capacity of gastric carcinoma (GC) cells and its molecular mechanism. Methods: Cancer and para-cancerous tissue samples resected from 50 GC patients, who were surgically treated in Wuwei People's Hospital from January 2016 to June 2019, were collected for this study; in addition, GC cell lines MGC803 and SGC7901 were also collected. qPCR was used to detect the HMGA2 expression in tissues and mRNA expressions of molecules related to cell proliferation, migration and invasion in GC cell lines. MGC803 and SGC7901 cells were transfected with pcHMGA2 by liposome transfection technology. After treatment with DDP and APA at different concentrations, the cells were divided into NC, pcHMGA2, pcHMGA2+DDP and pcHMGA2+DDP+APA groups. Protein expression of HMGA2 in GC cells was detected by Western blotting, and proliferation, migration and invasion of the cells were detected by MTT and Transwell assay, respectively. Results: The mRNA expression of HMGA2 in GC tissues was higher than that in para-cancerous tissues (P<0.05), and the survival rate of GC patients in the high expression group was significantly reduced (P<0.01). DDP significantly inhibited the proliferation, invasion and migration of MGC803 and SGC7901 cells (all P<0.01); the proliferation, invasion and migration of MGC803 and SGC7901 cells in DDP+APA group significantly decreased (all P<0.01) as compared with DDP group; APA significantly enhanced the inhibitory effect of DDP on HMGA2 expression in GC cells (P<0.01); APA enhanced the anticancer activity of DDP against GC by down-regulating HMGA2 expression. Conclusion: APA promotes the anticancer activity of DDP against GC, and its molecular mechanism is the promotion of the inhibitory effect of DDP on HMGA2 expression.